A sea of red-shirted protesters gathered at the corner of Las Vegas Boulevard and Sunset Road on Saturday to join in a global march against food giant Monsanto Co. and the right to know what’s in their food.

The crowd waved signs with the crossed-out acronym GMO (genetically modified organism), and booed every time Monsanto was mentioned. Passing cars honked their horns in support, and event organizers passed out pamphlets urging participants to call Sens. Dean Heller and Harry Reid.

“We have to speak in a language that they understand, and that’s profit,” Paul Graham, author of “Eating Vegan in Vegas,” shouted to the crowd.

Health-conscious eaters, concerned parents and their children, and big-corporation protesters gathered because they are disturbed by the potential health issues caused by genetically modified foods. They came to add their voices to a global rally against Monsanto.“All we’re trying to do is to show solidarity to the fact that we are (angry) and don’t want to deal with it anymore,” said Angie Morelli, the Las Vegas event’s coordinator. “They’re genetically modifying our food, and they’re not telling us the ramifications of it. Every time we do find out the ramifications of it, it’s horrible.”

Monsanto is a multinational agricultural biotechnology corporation, which sells genetically modified seeds. The seeds are designed to resist insecticides and herbicides, add nutritional benefits and improve crop yields.

Yet many people feel those genetically modified foods can lead to health problems. Some are frustrated with the government for its recent decision to vote down a bill that would have pushed for mandatory labeling of genetically modified organisms. In response, people from more than 250 cities and 35 countries decided to hold an International March Against Monsanto.

Morelli organized the Las Vegas event after she noticed 300 people had signed up on the Las Vegas March Against Monsanto Facebook page, but no one had taken charge. She was new to the cause — only learning about Monsanto and genetically modified food about six months ago — but she felt strongly about it and decided to take action.

“This is the one issue that affects everybody,” Morelli said. “There’s all these issues that affect a segment of the population, but this is the one thing that affects all of us and the world.”Protesters showed up wearing red in solidarity to march about one mile to the "Welcome to Fabulous Las Vegas" sign. The rally stretched about half of a mile down Las Vegas Boulevard during the march.

Laura Love attended the protest with her children. She said she has resorted to growing her own food in a garden and hunting in multiple grocery stores and farmers markets to ensure her children have food that hasn’t been genetically modified.

Emily Landers also attended the protest with her children and added that she has to research all her foods to check for GMOs before she feeds them to her kids. One of her daughters held a sign that read “Let Nature Grow, No GMOs.”

“I’m at the point where I don’t know what is safe to eat or feed my kids anymore,” Landers said.

Michael McCaslin dressed up in his Phantom Patriot costume (which resembles Captain America), to help attract attention to the issue. He uses his alter ego when he attends about one protest a month for causes that are important to him. He said this is the largest protest he’s attended since the Occupy movement.

“Realistically, we won’t shut Monsanto down,” McCaslin said. “At the very least, I hope it will lead to labeling of any GMOs on foods.”Morelli hopes people will take note of the issue and read more about it. After all, everyone eats.